Accurate Inertial Earth Rotation Measurements

The complex interaction between the fluids of the Earth and the solid Earth results in small variations in the rotational velocity of the Earth at the level of ∆Ω ≈ 10e-8, which are not predictable. These signals are usually observed utilizing the GNSS constellation and the global IGS receiver network. Stability is provided by the VLBI technique. Inertial Earth rotation sensing, based on ring laser gyroscopes, is now capable of detecting these signals with high temporal resolution. Therefore it is important to closely examine the inherent accuracy of the utilized gyroscope technology.  This presentation outlines the latest improvements in sensor operation, reviews some crucial sensor properties and puts them into perspective with the established techniques in space geodesy.